Duodenal switch

 Also known as Bilio-Pancreatic Diversion with Duodenal Switch or the DS.

In Duodenal Switch, a larger portion of the stomach is left intact, including the pyloric valve that regulates the release of contents from the stomach into the small intestine. The duodenum is divided near this valve, and the small intestine divided as well. The portion of the small intestine connected to large intestine is attached to the short duodenal segment next to the stomach. The remaining segment of the duodenum connected to the pancreas and gallbladder is attached to this limb closer to the large intestine. Where contents from these two segments mix is called the common channel, which dumps into the large intestine.

To prevent deficiencies, a high-protein diet and lifelong vitamin and mineral supplementation are necessary.

In Duodenal switch  gastrointestinal tract is altered  with two approaches:

1.  Restrictive aspect 

2. Malabsorptive aspect

 1.  Restrictive aspect

In restrictive aspect, the surgery reduces the stomach along the greater curvature so that the volume is approximately 1/3 (33%)  to 1/5 (20%) of the original capacity. 

2. Malabsorptive aspect

The objective of this arrangement is to reduce the amount of time the body has to capture calories from food in the small intestine and to selectively limit the absorption of fat.

 In the malabsorptive aspect of the surgery reroutes a lengthy portion of the small intestine, creating two separate pathways and one common pathway.

The shorter of the two pathways, the digestive loop, takes food from the stomach to the large intestine. The much longer pathway, the bilio-pancreatic loop, carries bile from the liver to the common path.

The common path, or common channel, is a stretch of small intestine usually 75-150 centimeters long in which the contents of the digestive path mix with the bile from the bilio-pancreatic loop before emptying into the large intestine.

Advantages of the Duodenal Switch (DS)

Duodenal Switch (DS) surgery is a combination of moderate intake restriction with substantial calorie malabsorption results in a very high percentage of excess weight loss for obese individuals, with a very low risk of significant weight regain.

Because the pyloric valve between the stomach and small intestine is preserved, people who have undergone the DS do not experience the dumping syndrome common with people who've undergone the Roux-en-Y gastric bypass surgery (RNY).

The chance of developing anastamotic stricture (common with the RNY) is extremely low.

Much of the production of the hunger hormone, Ghrelin, is removed with the greater curvature of the stomach.

Diet following the DS is more normal and better tolerated than with other surgeries.

Those who undergo the DS often find that comorbidities such as high blood pressure, diabetes mellitus type 2, and arthritis are significantly relieved in a short time after the surgery.

Type 2 Diabetes is "cured" - or put into remission - in the large majority of patients having the DS. These benefits occur long before great losses in weight are seen. Some surgeons do the "switch" or intestinal surgery on non-obese patients for the benefits of curing the diabetes.

Some surgeons are so confident in the benefits of the DS that they will accept super-morbidly obese patients, who are often turned down for other weight loss surgeries; however, anyone who qualifies with a body mass index (BMI) of 40 or a BMI of 35 with comorbidities qualifies for the more successful DS surgery.

Patients with BMI of 35 or over with obesity-related illnesses such as:
    * Diabetes mellitus type 2
    * Coronary heart disease
    * Sleep apnea
    * Osteoarthritis

 are qualified for Duodenal switch.

Disadvantages of the Duodenal Switch (DS)

Far fewer surgeons perform the DS compared to other weight loss surgeries because it is a more difficult one to learn compared to RNY and Lap Band procedures

 The malabsorptive element of the DS requires that those who undergo the procedure take vitamin and mineral supplements above and beyond that of the normal population, as do patients having the RNY surgery. Commonly prescribed supplements include a daily prenatal vitamin and extra calcium citrate.

Because gallstones are a common complication of rapid weight loss following any type of weight loss surgery, some surgeons may remove the gall bladder as a preventative measure during the DS or the RNY. Others prefer to prescribe medication to reduce the risk of post-operative gallstones.